Investigation into Techniques for the Determination of Moisture Content onActivated Carbon

摘要

The current method employed in the determination of the moisture content ofactivated carbon is the American Standard Test Method (ASTM) D-2867 (1976), using xylene extraction. However, this test is time-consuming and requires an elaborate experimental set-up. Furthermore, the ASTM has been found to be unsuitable for ASC/T carbon which contains triethylenediamine (TEDA). For this reason, alternatives to the ASTM were considered in this study. The ASTM method has been modified by replacing the extracting solvent xylene with toluene, to reduce the quantity of TEDA being collected with the water. Another alternative is the use of a convection oven where carbon samples were dried under three conditions: 150 C for 3 hours, 105 C for 3 hours and 105 C for 16 hours, and the moisture content results compared. This alternate method proves to be more efficient and the results obtained are comparable to that of the ASTM method. The optimum drying conditions for the accurate determination of moisture content on BPL, ASC and ASC/T carbons were determined to be 105 C for 60 minutes, 150 C for 90 minutes and 105 C for 90 minutes respectively. The last alternative considered was the use of a thermal analytical technique, namely Differential Scanning Calorimetry (DSC). It has been determined in this study that DSC can be used as an analytical tool for the determination of moisture content on carbons. However, better resolution of the DSC thermogram is required for precise measurements in moisture content determination.